Multiband guiding structures for antennas and methods for using the same are described. In one embodiment, an antenna comprises: an antenna aperture with radio-frequency (RF) radiating antenna elements; and a center-fed, multi-band wave guiding structure coupled to the antenna aperture to receive a feed wave in two different frequency bands and propagate the feed wave to the RF radiating antenna elements of the antenna aperture.

Multiband guiding structures for antennas and methods for using the same are described. In one embodiment, an antenna comprises: an antenna aperture with radio-frequency (RF) radiating antenna elements; and a center-fed, multi-band wave guiding structure coupled to the antenna aperture to receive a feed wave in two different frequency bands and propagate the feed wave to the RF radiating antenna elements of the antenna aperture.

A microwave prism is used to repoint an operational Direct-to-Home (DTH) or Very Small Aperture Terminal (VSAT) reflector antenna as part of a ground terminal to receive (or transmit) signals from a different satellite or orbital position without physically moving the reflector or the feed horn antenna. The microwave prism operates by shifting the radiated fields from the horn antenna generally perpendicular to the focal axis of the parabolic reflector in order to cause the main beam of the reflector to scan in response. For an existing reflector antenna receiving signals from an incumbent satellite, a prism has been designed to be snapped into place over the feed horn and shift the fields laterally by a calibrated distance. The structure of the prism is designed to be positioned and oriented correctly without the use of skilled labor. This system allows a satellite service provider to repoint their subscribers to a new satellite by shipping a self-install kit of the prism that is pre-configured to have the correct orientation and position on the feed antenna to correctly re-point the beam at a different satellite once the prism is applied. One benefit of the system is that unskilled labor, i.e., the subscribers themselves, can be used to repoint a large number of subscriber antennas in a satellite network rather than requiring the cost of a truck roll and a technician to visit every site. The microwave prisms to implement this functionality can be constructed in different ways, with homogeneous slabs or blocks, Gradient-Index (GRIN), multi-layered dielectric, geometric or graded-index Fresnel-zone, metasurface, or metamaterial prisms. The geometric and electrical constraints of the design are determined by the incumbent and target satellites, and the ground terminal location.

This document describes techniques, apparatuses, and systems for a wave-shaped ground structure for antenna arrays. A radar system may include a ground structure with a first surface having a wave shape and a second surface opposite the first surface. The ground structure includes multiple antenna arrays separated in a longitudinal direction on the first surface. Each antenna array includes one or more antenna elements configured to emit or receive electromagnetic (EM) energy. The ground structure also includes antenna feeds separated in the longitudinal direction on the second surface and operably connected to the antenna arrays. The wave shape of the ground structure configures the radar system to provide an antenna radiation pattern that provides a uniform radiation pattern among the antenna arrays. The wave shape can also be configured to provide an asymmetrical radiation pattern or a narrow beamwidth for specific applications.

The disclosed structures and methods are directed to antenna systems configured to transmit and receive a wireless signal in and from different directions. A switchable lens antenna has excitation ports radiating radio-frequency (RF) wave into a parallel-plate waveguide structure, and a frequency selective structure (FSS). The antenna presented herein is configured to operate in two modes depending on an initial steering angle of the RF wave propagating in the parallel-plate waveguide structure. When the initial steering angle is about or less than a threshold steering angle, FSS is OFF due to its stubs being electrically disconnected from the parallel-plate waveguide structure. When the initial steering angle is higher than the threshold, FSS is ON with stubs being electrically connected to the parallel-plate waveguide structure. When ON, FSS provides phase variance to the RF wave propagating in the parallel-plate waveguide structure and increases steering angle of the RF wave.

The disclosed structures and methods are directed to antenna systems configured to transmit and receive a wireless signal in and from different directions. A switchable lens antenna has excitation ports radiating radio-frequency (RF) wave into a parallel-plate waveguide structure, and a frequency selective structure (FSS). The antenna presented herein is configured to operate in two modes depending on an initial steering angle of the RF wave propagating in the parallel-plate waveguide structure. When the initial steering angle is about or less than a threshold steering angle, FSS is OFF due to its stubs being electrically disconnected from the parallel-plate waveguide structure. When the initial steering angle is higher than the threshold, FSS is ON with stubs being electrically connected to the parallel-plate waveguide structure. When ON, FSS provides phase variance to the RF wave propagating in the parallel-plate waveguide structure and increases steering angle of the RF wave.

A lens according to the disclosure includes a dielectric having a first surface and a second surface that is spaced from the first surface and that faces the first surface in a direction of a reference axis intersecting the first surface. The dielectric has an equivalent relative dielectric constant that decreases in a direction from the reference axis toward outer circumferences of the first surface and the second surface.

A lens according to the disclosure includes a dielectric having a first surface and a second surface that is spaced from the first surface and that faces the first surface in a direction of a reference axis intersecting the first surface. The dielectric has an equivalent relative dielectric constant that decreases in a direction from the reference axis toward outer circumferences of the first surface and the second surface.

A microwave prism is used to repoint an operational Direct-to-Home (DTH) or Very Small Aperture Terminal (VSAT) reflector antenna as part of a ground terminal to receive (or transmit) signals from a different satellite or orbital position without physically moving the reflector or the feed horn antenna. The microwave prism operates by shifting the radiated fields from the horn antenna generally perpendicular to the focal axis of the parabolic reflector in order to cause the main beam of the reflector to scan in response. For an existing reflector antenna receiving signals from an incumbent satellite, a prism has been designed to be snapped into place over the feed horn and shift the fields laterally by a calibrated distance. The structure of the prism is designed to be positioned and oriented correctly without the use of skilled labor. This system allows a satellite service provider to repoint their subscribers to a new satellite by shipping a self-install kit of the prism that is pre-configured to have the correct orientation and position on the feed antenna to correctly re-point the beam at a different satellite once the prism is applied. One benefit of the system is that unskilled labor, i.e., the subscribers themselves, can be used to repoint a large number of subscriber antennas in a satellite network rather than requiring the cost of a truck roll and a technician to visit every site. The microwave prisms to implement this functionality can be constructed in different ways, with homogeneous slabs or blocks, Gradient-Index (GRIN), multi-layered dielectric, geometric or graded-index Fresnel-zone, metasurface, or metamaterial prisms. The geometric and electrical constraints of the design are determined by the incumbent and target satellites and the ground terminal location.

A planar conductive millimeter-wave lens includes: a planar conductive plate with a first surface and a second surface, wherein the first surface is parallel to the second surface; a plurality of openings from the first surface through the planar conductive plate to the second surface, where an axis of each opening is perpendicular to the first surface and the second surface. A size of each opening is a function of a position of said each opening on the planar conductive plate such that an insertion phase collectively imposed by the openings on an incident wave causes the incident wave to pass through the first surface and the planar conductive plate, exit from the second surface and to focus at a predetermined distance from the second surface.